1. Field of the Invention
The present invention relates to a gate driving circuit and a display apparatus having the gate driving circuit. In some embodiments, the gate driving circuit is capable of reducing driving defects.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) apparatus includes an array substrate, a counter substrate and a liquid crystal layer disposed between the array and counter substrates. The liquid crystal layer includes liquid crystal molecules having an anisotropic dielectric constant. In the LCD apparatus, an electric field is applied to the liquid crystal molecules and light transmissivity is controlled according to the intensity of the electric field to display an image.
The LCD apparatus includes a display panel containing the array and counter substrates and further includes a gate driving circuit and a data driving circuit. The display panel includes a plurality of pixel areas defined by gate lines and data lines transverse to the gate lines. The gate driving circuit outputs gate signals to the gate lines, and the data driving circuit outputs data signals to the data lines. Generally, the gate and data driving circuits are formed as integrated circuit chips mounted on the display panel.
To decrease the LCD size and increase productivity, the gate driving circuit can be integrated directly on the display substrate. However, when such an integrated gate driving circuit is operated at high temperatures, noise can be generated in the form of an abnormal gate-on signal occurring in gate-off time.
The noise is generated due to parasitic capacitance (Cgd) between a clock signal and the gate of a pull-up transistor. This capacitance serves to increase the transistor's gate voltage when the transistor is supposed to be off. At the same time, the high temperature drives up the transistor's leakage current. As a result, the pull-up transistor turns on. The intermittent abnormal turning-on of the pull-up transistor causes display defects on the LCD.